The simplest way to edit a PDF on Mac is Preview, the app already built into your computer

You do not need to buy software or read anything. Open the PDF in Preview (the default when you double-click a PDF file), click the markup toolbar icon in the top right, and you can add text, draw, highlight, or sign directly on the page. Preview saves your changes to the same file unless you choose "Save As" to keep the original untouched.

Preview works well for common edits: filling in forms, adding notes, striking through text, or inserting your signature. It does not let you rearrange pages, change fonts, or edit the original text that was already in the PDF — only add new content on top. If you need those deeper changes, you will need a different tool.

Key Takeaways

  • Preview is built into every Mac and handles basic edits like adding text, highlighting, and signing without any cost or read.
  • The markup toolbar in Preview lets you add shapes, lines, text boxes, and your signature directly onto any page.
  • Preview cannot edit text that was already in the PDF or rearrange pages — it only adds content on top of the existing document.
  • If you need to edit original text, remove pages, or change the PDF structure, you will need software like Adobe Acrobat Pro or a free alternative like PDFtk.

How to open the markup toolbar in Preview

Open your PDF in Preview by double-clicking it, or by right-clicking it, selecting "Open With," and choosing Preview. Once the PDF is open, look at the top right of the window. You will see a toolbar icon that looks like a pen tip in a circle — click it to reveal the markup tools.

The toolbar shows you options to add text, draw freehand, insert shapes, highlight, underline, or strike through text. You can also add your signature by clicking the signature icon, then choosing "Manage Signatures" to create one the first time. Each tool stays active until you click a different one, so you can add multiple text boxes or drawings without reopening the menu.

Adding text and filling in forms

Click the text tool (the "A" icon) in the markup toolbar, then click anywhere on the page where you want to add text. A text box appears and you can type. Adjust the font size and color using the options that appear below the toolbar. When you are done with that text box, click elsewhere on the page to start a new one or click a different tool.

For PDF forms with blank fields, click inside each field and type your answer. Preview treats each field as a separate text box, so you can move between them by clicking. If the form was created as a fillable PDF, Preview will recognize the fields automatically. If it is a scanned form or an image-based PDF, you can still add text anywhere — it just will not snap to the field boundaries.

Highlighting, underlining, and striking through text

Select the text you want to mark by clicking and dragging across it. Once the text is highlighted in blue, use the markup toolbar to choose highlight, underline, or strikethrough. The color defaults to yellow for highlighting, but you can change it by clicking the color circle next to each tool.

These tools only work on text that is selectable — meaning text that was typed or created as actual text in the PDF, not scanned images. If you are working with a scanned document or an image-based PDF, you cannot select and mark the text this way. Instead, use the drawing tool to manually highlight or underline by hand.

Drawing and adding shapes

The sketch tool (pen icon) lets you draw freehand on the page. Click it, then click and drag to draw lines, circles, or any shape you want. The line thickness and color are adjustable in the toolbar. Use this to circle important information, draw arrows pointing to sections, or add visual notes to the document.

If you want straight lines or geometric shapes, use the shapes tool (the rectangle icon) instead. Click it, then drag on the page to create a rectangle, circle, or line. You can adjust the line weight and color before or after drawing. Shapes are useful for boxing in sections of a form or creating visual separations between your notes.

Signing a PDF in Preview

Click the signature tool (looks like a pen writing) in the markup toolbar. If this is your first time signing a PDF on this Mac, click "Manage Signatures" and choose to create a new signature. You can draw your signature with your trackpad or use your iPhone camera to photograph your handwritten signature — the camera method usually looks more natural.

Once your signature is saved, you can click the signature tool again and straightforward click on the page where you want it to appear. The signature is inserted at full size, but you can resize it by dragging the corners. You can add the same signature to multiple pages without recreating it each time.

Saving your changes and keeping the original

When you finish editing, Preview saves your changes automatically to the same file. If you want to keep the original PDF untouched and save your edited version separately, go to File > Save As, give it a new name, and choose where to save it. This creates a second file with your edits while leaving the original alone.

You can also export the PDF in a different format if needed — go to File > Export and choose PDF, JPEG, PNG, or TIFF. Exporting as JPEG or PNG converts the PDF to an image, which is useful if you want to share it in a format that cannot be edited further, but you lose the ability to select text or make future changes.

When you need more than Preview can do

Preview cannot edit text that already exists in the PDF, rearrange or delete pages, change fonts, or compress file size. If your task requires any of these, you have two paths: paid software or free alternatives.

Adobe Acrobat Pro is the industry standard and costs about $180 per year. It lets you edit original text, rearrange pages, add or remove content, and handle complex forms. PDFtk is free and open-source software that handles page rearrangement, splitting, and merging from the command line — useful if you are comfortable with terminal commands. Coherent PDF (formerly cpdf) is another free command-line tool for page manipulation. For simpler needs like merging or splitting PDFs, Preview itself can do this — open multiple PDFs, drag pages between them, and save the result.

Frequently Asked Questions

Can I edit text that was already typed in the PDF?

No, Preview cannot edit existing text. You can only add new text on top of the document. If you need to change words that are already in the PDF, you need Adobe Acrobat Pro or a similar tool designed for text editing.

How do I delete a page from a PDF in Preview?

Open the PDF in Preview, click View > Thumbnails to see all pages as small images on the left side, right-click the page you want to remove, and select Delete. Save the file when you are done. This permanently removes the page from that PDF.

Can I merge two PDFs together in Preview?

Yes. Open both PDFs in Preview, click View > Thumbnails in each one, then drag pages from one PDF's thumbnail panel into the other. Save the file with the new pages added. This is faster than using separate merging software for straightforward jobs.

What if my PDF is a scanned image and I cannot select the text?

Scanned PDFs are images, not text. Preview cannot select or edit the text in them. You can still add your own text, highlights, and drawings on top using the markup tools. If you need to edit the actual scanned text, you would need optical character recognition (OCR) software, which converts images of text into selectable text.

Does Preview work the same way on iPad?

Yes, iPad has a version of Preview in the Files app, and you can also use the Markup tools in the Notes app or Mail app to edit PDFs. The tools are similar but the interface is touch-based instead of trackpad-based. Saving works the same way — changes save automatically unless you choose Save As.